XSS in Wire Server
CVE-2021-41101
wire-server is an open-source back end for Wire, a secure collaboration platform. Before version 2.106.0, the CORS ` Access-Control-Allow-Origin ` header set by `nginz` is set for all subdomains of `.wire.com` (including `wire.com`). This means that if somebody were to find an XSS vector in any of the subdomains, they could use it to talk to the Wire API using the user's Cookie. A patch does not exist, but a workaround does. To make sure that a compromise of one subdomain does not yield access to the cookie of another, one may limit the `Access-Control-Allow-Origin` header to apps that actually require the cookie (account-pages, team-settings and the webapp).
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.007 (51.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
- Wire Server
- Wireapp Wire-Server — versions < 2.106.0
Weakness classification (CWE)
References
- github.com/wireapp/wire-server/security/advisories/GHSA-v7xx-cx8m-g66p (Third Party Advisory)
Frequently asked questions
- What is CVE-2021-41101?
- CVE-2021-41101 is a medium-severity vulnerability in Wire Server, classified under Cross-site Scripting. CVSS score: 5.7/10. Published 2021-09-30.
- How severe is CVE-2021-41101?
- Medium severity. CVSS v3 base score is 5.7 out of 10.